1. Field of the Invention
The present invention relates generally to exercise machines and more particularly to an exercise machine that has a pulley arrangement that allows for varying the mechanical advantage provided by traditional pulley exercise machines.
2. Related Art
Various exercise machines for strength training are well known in the art including machines that utilize a weight stack and pulley system to provide resistance to an exercise movement. A typical exercise machine has a frame, a load or some means to provide resistance mounted on the frame, and multiple exercise outlets functionally connected to the load. Pulleys and cables are the most common method used to functionally connect the load to the exercise outlets. Pulley and cable exercise machines provide mechanical advantages to the exerciser using the machine. The mechanical advantage can be positive, negative or neutral. The mechanical advantages are a result of understood principals of physics.
A typical cable and pulley set up employs a first cable connected at a first end to a load and at a second end to a first pulley. A second cable is connected at a first end to a first exercise station. A second end of the second cable engages a second pulley, then engages the first pulley, then a third pulley before finally being fixed to the frame. This pulley configuration allows the exerciser to provide a force of 50% of the load to lift the load. The mechanical advantage in the above pulley arrangement is in the ratio of 1 to 2. The addition or subtraction of pulleys alters the mechanical advantage realized by the exerciser.
Many exercise machines are designed for use in areas that are either multipurpose or smaller than a traditional gymnasium, for example, a home or apartment. With these area restrictions it has become increasingly more important to conserve space by reducing the size of the exercise machines as well as incorporating multiple functions into one machine. Many of the prior inventions, for example, provide an exercise machine that allows an exerciser to perform different exercise movements using a single weight stack. This arrangement of multiple exercise outlets and a single weight resistance module is accomplished by providing multiple cable and pulley systems that are operable independent of one another. Previous pulley arrangements incorporate a fixed mechanical advantage which is predetermined by the number and position of the pulleys in the system.
The exerciser, therefore, is limited to changing resistance levels in fixed increments determined by how much each weight of the stack weighs. For example, if the pulley system allows for a 1 to 2 ratio and each plate in the stack weighs 20 pounds, the exerciser can change the resistance only in 10 pound increments. For an exerciser to increase the resistance by less than a full 10 pounds, for example by 5 pounds, he or she must add a xe2x80x9csupplemental weightxe2x80x9d to the stack. Previously used supplemental weights have taken the form of a small weight that is selectively removable from storage on a peg on the frame and is placed onto an aligned peg on the top plate of the weight stack. The separate supplemental weight design is counter to the advantages of using a simplified unitary stack for resistance. Furthermore, incorporating a separate supplemental weight can result in the supplemental weight being lost or removed from the exercise station, requiring the exerciser to break from his or her routine in order to utilize it. Additionally, much of the cost associated with exercise machines of this type is for the weights used for resistance. The additional purchase of the supplemental weights further increases the cost of the exercise machine. A second form of a supplemental weight is fixed small weights either on an arm or on a guide rod that provides a path to place the supplemental weight onto the main stack. These supplemental weights can be selectively engaged by sliding the supplemental weight onto the weight stack. This approach also requires the inclusion of additional, separate weight units, adding cost to the exercise machine.
Other exercise machines have been developed that allow for multiple weight ratios. Specifically, a pulley arrangement comprising two floating pulleys that allow for an exercise machine to contain multiple exercise stations having varying mechanical advantages. Devices of this type, however, require the use of different exercise stations to vary the weight ratio. This changing of the exercise stations does not provide the ability of the exerciser to choose a varied weight ratio while exercising at the same station.
The purpose and advantages of the invention will be set forth in and apparent from the description and drawings that follow, as well as will be learned by practice of the invention. Additional advantages of the invention will be realized and attained by the elements of the apparatus and method described.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, a new and useful exercise machine is provided. In accordance with one aspect of the invention, the dual adjustable pulley system includes a frame, weight stack, pulleys, and cables. The weight stack is slidably connected to the frame. A primary moveable pulley system is functionally engaged with the weight stack by way of a primary cable. The primary cable has a handle, or other apparatus, connected to its first end and its second end is fixed with respect to an exercise movement. A series of directional pulleys are also engaged by the primary cable. The directional pulleys are positioned on the frame to allow for an exerciser to perform multiple exercises employing the weight stack. A secondary moveable pulley system is functionally connected with the primary moveable pulley system. The secondary moveable pulley system is selectively engaged with the weight stack using a releasable coupler. A secondary cable is functionally engaged with the secondary moveable pulley system and a number of directional pulleys. The secondary cable has a first end that is fixed to a floating pulley. The floating pulley is functionally engaged with the primary cable. The secondary cable has a second end that selectively engages the weight stack. The relationship between the primary moveable pulley system and the secondary moveable pulley system is such that when the handle is moved in an exercise motion, the weight stack provides resistance to the exercise motion.
In another aspect of the invention, the secondary moveable pulley system can be selectively engaged with the weight stack such that it allows the exerciser to select varying increments of weight to be lifted. The invention provides that when the secondary moveable pulley system is disengaged, the floating pulley will remain in a fixed vertical position and, as a result, the first moveable pulley system will provide a predetermined mechanical advantage to the exerciser lifting the selected number of weights from the weight stack. For example, in a pulley arrangement that provides a 1 to 4 mechanical advantage an addition of a 20 pound plate will effectively increase the load by 5 pounds.
According to the invention, if the secondary pulley arrangement is engaged, the mechanical advantage will be reduced. This decrease in mechanical advantage is achieved by engaging a releasable coupling to a bayonet which in turn causes the floating pulley to move down as the bayonet moves up. For example, if the first pulley arrangement provided a 1 to 4 mechanical advantage, the engagement of the secondary pulley arrangement would decrease the mechanical advantage to 1 to 2. Therefore, if an additional plate of 20 pounds was added to the stack it would effectively increase the load by 10 pounds.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and provided for purposes of explanation only, and are not restrictive of the invention. In particular, while various aspects and advantages of the instant invention have been described above and will be described below, the invention is not limited thereto and other aspects and advantages, as will be apparent from the entirety of the present specification, exist.